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laddy
01-17-2009, 09:28 PM
Hey,
Anybody using the shooting star Dro system?? Would love to hear a few comments before investing in it. Thanks in advance Fred

japcas
01-17-2009, 10:03 PM
I've had one on my mill for about 3 years and one on my lathe for about one year. I like it a lot. It is plenty accurate for my needs and seems to be very repeatable. They have several features on them like the more expensive dros do like center find, bolt hole and bolt line, and up to 99 presets can be entered in. I've been very pleased with them and don't regret buying them. I wouldn't mind to have Newall C80's but they cost about $1000 more per dro so I can't complain.

Pherdie
01-17-2009, 10:21 PM
I've had one (two axis version) for about six or seven years. It has never malfunctioned and provided repeated accuracy. When I purchased the unit, it seemed to be the best 'bang' for my limited buck, as glass scale based units were typically priced much higher.

Originally it was mounted on a Rong-Fu 45 mill drill. When I upgraded the mill to a Bridgeport, the Bridgeport came equipped with a Sony system. I then decided to purchase another rack from Shooting Star (no problems there) and mount the Shooting Star on my Jet GHB-1340A. The purchase of an additional rack was driven by the fact that the original racks had been cut for the Rong-Fu and one was now too short to properly fit the lathe.

In retrospect, some of the current crop of glass scale units appear to meet Shooting Star on pricing and had I to make the decision again, I would most likely go for a glass scale unit. That's only because I have more faith in a glass scale system for accuracy, longevity and trouble free operation over the long haul (less mechanics).

I have found the Shooting Star system to be a reliable, trouble free and quite importantly, a WELL SUPPORTED system. Big points for support when things go bad!

Fred

randyjaco
01-17-2009, 10:47 PM
I have had the a 3 axis model on my mill for about 7 years. It has been a great unit. I had one axis go out a couple of years ago, post warranty. I called Shooting Star expecting to have to buy a new gear box and they sent me the whole axis assembly free of charge. Their service is great.

It may not be the ultimate in accuracy, but it is more than enough for me. For the money it can't be beat.

danlb
01-18-2009, 02:07 AM
I found this thread right after buying a glass scale version from shars.com. It has all the features noted above (bolt circles, etc) and is about the same price as the one from shooting star.

I was surprised to see the shooting star accuracy was only .002 per foot.

I would like the skinnier racks of the shooting start unit. The glass scales are almost an inch thick, and 2 inches high (including the reader unit).

Dan

torker
01-18-2009, 02:42 AM
Yup...you'll get plenty of arguments over this.
The glass units are much cheaper now.
I've had a SS for a few years now and I still love it.
Accuracy... .002 per foot...ya...that's what it says.
However...I tried mine against the dials on my X screw for the whole table travel. The dro was bang on with the screw for the whole table travel...turn for turn...the whole distance!
I've drilled a few dozen bolt circles with it now...the cutter or drill goes in the second time around with nary a touch,
I'm really happy with mine.
And the service is second to none. If I need parts..I can have them here overnight.
Russ

John Stevenson
01-18-2009, 07:29 AM
I can't comment on the shooting star brand as I have never used it or seen it, only read the web blurb.

We had a similar system over here in the UK and it fitted in well with the home shop guys as regards easy to fit [ size ] and price. Again limited to 2 thou per foot.

Compared to glass scales they were 1/3 the price.

However over the years as costs went up so did this cheap DRO, accuracy and repeatability stayed the same but the glass scales came down in price.

I bought one and it cost 330 for a 2 reader head and two 'scales' only a few months after I had bought a Heidenhain new for about 1300.

It wasn't up to the standard of the Heidenhain but it was passable.

Now fast forward to today, this cheap DRO got up to 380 before it was removed from the market. last year I had the option of buying an Onxy 2 axis DRO with ANY two length scales for 350.
I chose to buy a 3 axis with ANY 3 scales for 400 tax paid and fit one to the knee later.

This year I bought a Sino 2 axis DRO but with only one scale for the cross slide on a lathe for 220

Service on these are good but only limited to the statuary one year so after than like most things you are on your own. Worse case scenerio is that any one unit is about 100 so if you say I have put 100 aside as insurance over the next 20 years that's one way to look at it.

.

torker
01-18-2009, 09:32 AM
John..I've read your thoughts about these SS dro's many times over the past few years.
Geez...what you just said...you could almost buy two Sinos for the price of one SS.
I'm going to stick with SS dro's for my mills but if I ever go the dro route on a lathe I think I'm going to go with a glass scale setup.
Because I live so close to where they (SS)are made it's a huge factor in my support for them
If I need to change it over to another machine...I can have new racks here overnight for $100 each.
I cut them as long as I can anyway so I'd be ok with anything but the biggest mill.
Russ

ammcoman2
01-18-2009, 09:43 AM
I have had one on my 8 x 30 knee mill for about 3 years now. It is the older style and I bought it 2nd hand (it was new but had never been installed).

No hiccups so far, easy to cut the rods to size and reasonably easy to install. The split covers over the rods seem to do their job but I did put the extra covering (Al angle) over the top of the X and Y axis rods.

I did a mini calibration test after setting it up using an 8" micrometer calibration rod as the standard and there was no error showing on the display. I didn't check for accuracy over the whole length of table travel, though.

That said, I agree with John that the price may no longer be competitive. I would have to think long and hard if I were to to consider one now.

One thought is to get a 2 axis unit and a Bridgeport style stand-alone for the quill thereby keeping the cost down.

Geoff

danlb
01-18-2009, 01:33 PM
One of the advantages I note with the SS systems is that you can cut the rack to fit the travel that you need.

I've not seen anything about cutting or altering the glass scales. I must admit that I did not look too hard for that info. :)

I was wondering where they get that .002 rate... Maybe to account for worst case thermal expansion? It seems that sInce the rack meshes with the gear, the only other way to get very far off is to have a badly cut rack or gears in the reader.

Dan

barts
01-18-2009, 02:41 PM
I was wondering where they get that .002 rate... Maybe to account for worst case thermal expansion? It seems that sInce the rack meshes with the gear, the only other way to get very far off is to have a badly cut rack or gears in the reader.
Dan

Cumulative mechanical error during rack generation... yes, it's possible to build racks w/o this error, but it's very expensive - ground racks, ground gears, closely temp. controlled grinding machines, etc.

I once led the software effort to control a 30' long CMM; the only cost-effective way of location position at the time (1986) was a precision rack. We measured the errors vs position w/ a laser interferometer, and error-mapped each axis, and used that data in all the kinematics calculations. Calibration was a major PITA, and needed to be redone when a traumatic event occurred, such as a collision w/ the 2000+ lb part being inspected... this involved a trip to Aberdeen, S.D. with $25k worth of laser optics and a lot of patience.

Reed
01-18-2009, 05:50 PM
*** disclaimer; I'm not a job shop.

As above I have 3 which are the old style. Two are 3 axis and one is 2 axis. I've been using these for better than 8 years or so.

I had one service call and the damage was my fault, it was an installation foobarr where I fumbled and let the encoder spin on the rack. I explained that and the reply was no problem as it was their policy to R&R. One was sent out.

About the 2 thou per foot. I found it to be well within that while doing inspection on work that had shoulders 10" apart where the error was less than 1/2 thou.

YMMV, but I've been happy with it.

- Reed

PHiers
01-18-2009, 07:21 PM
I have the shooting stars on both my mill and lathe. I have been using them for about 5 years and really have not had problem one. I also like the fact that they are made in North America. I think the .02 per foot is some worst case scenario.

MikeHenry
01-18-2009, 07:26 PM
I've had a Shooting Star 3-axis DRO on my Clausing mill for 5+ years now and it has never failed me. The accuracy is claimed at 0.002" per foot and tha's about what I measured a few years back with gage blocks and a DTI. AIR it was pretty linear across the range.